In 1850, Edward Coke stepped inside London’s Lock & Co. haberdashery, which had already been in business for almost 200 years, and made a rather novel request.

The farmer asked the hatters to devise a new kind of hat for him, one that would protect his gamekeepers’ heads from pesky overhanging branches and wouldn’t blow off at the first slight gust of wind. Lock handed the commission over to Thomas and William Bowler. A short while later, back at the shop on St. James’ Street, Coke tested out the success of the prototype by jumping on it. Luckily for the Bowlers, and the history of hats as we know it, the hat withstood his weight, Coke bought it, and sixty thousand of its kind were soon being sold each year.

Established in 1676, Lock’s claims to be the oldest hat shop in the world. It still has the original cardboard pattern used to fashion Lord Admiral Nelson a cocked hat in 1800, and a ledger bearing Winston Churchill’s name. Lord Byron, Oscar Wilde, Charlie Chaplin and Clark Gable were all kitted out by the shop, which displays their framed head templates to this day.

The most intriguing item is, and never was, for sale. Looking like a cross between a torture device and something stolen from the props department of a Tim Burton movie, the conformateur has been used to measure customers’ heads for over 100 years. It maps the shape of their skull by punching pins into paper and cards, making a template of the head at a reduced scale. You’d have to be mad as a hatter to use a measuring tape after seeing this contraption.